Present hollow forming method mainly includes injection molding, blow molding, rotational molding, gas injection molding, fusible core molding and so on, the advantage and disadvantage analysis between the above method is: 1) For blow molding: advantage: simple technology, low fabrication cost and high production ability, thick product wall, wide range for adjustment, easy to fabricate big volume hollow product with thin wall; disadvantage: limited in material used, not high quality of product outer surface, with cold material scar, uneven wall thickness in non-circular product production; 2) For rotational molding: advantage: suitable for product of small batch and big volume, more beautiful of product appearance than blow molding, wall thickness uniformity and controllability both excellent; disadvantage: limited in material utilization, long molding cycle, high cost, big dimension error; 3) For gas-assisted injection molding: advantage: with same quality of product outer surface as injection molding, smaller internal stress and less material usage, wide material utilization range; disadvantage: not suitable for thin wall product fabrication, difficult in controlling and leading product inner gas path, big thickness difference in the location of gas path turning around, long molding cycle; 4) For fusible core molding: advantage: simplified the mould from complication, with precise inner dimension of hollow product, with same quality of product outer surface as injection molding; disadvantage: Before production, prepared low temperature metal fusible core should be placed in the mould, then, taking heating method to melt the core and clean residue, fabrication cost is high, due to melted flow impacting on the core during molding process, it's not applicable for certain hollow product without suitable supporting in the hole, additionally more requirement in material lead to unable to be wildly used.